net: modify core data structures for PSP datapath support

Add pointers to psp data structures to core networking structs,
and an SKB extension to carry the PSP information from the drivers
to the socket layer.

Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Co-developed-by: Daniel Zahka <daniel.zahka@gmail.com>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250917000954.859376-4-daniel.zahka@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

8 files changed, 31 insertions, 0 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 62e7addccdf6..78ecfa7d00d0 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -4902,6 +4902,9 @@ enum skb_ext_id {
 #if IS_ENABLED(CONFIG_MCTP_FLOWS)
 	SKB_EXT_MCTP,
 #endif
+#if IS_ENABLED(CONFIG_INET_PSP)
+	SKB_EXT_PSP,
+#endif
 	SKB_EXT_NUM, /* must be last */
 };
 
diff --git a/include/net/inet_timewait_sock.h b/include/net/inet_timewait_sock.h
index 67a313575780..c1295246216c 100644
--- a/include/net/inet_timewait_sock.h
+++ b/include/net/inet_timewait_sock.h
@@ -81,6 +81,9 @@ struct inet_timewait_sock {
 	struct timer_list	tw_timer;
 	struct inet_bind_bucket	*tw_tb;
 	struct inet_bind2_bucket	*tw_tb2;
+#if IS_ENABLED(CONFIG_INET_PSP)
+	struct psp_assoc __rcu	  *psp_assoc;
+#endif
 };
 #define tw_tclass tw_tos
 
diff --git a/include/net/psp/functions.h b/include/net/psp/functions.h
index 074f9df9afc3..d0043bd14299 100644
--- a/include/net/psp/functions.h
+++ b/include/net/psp/functions.h
@@ -5,10 +5,16 @@
 
 #include <net/psp/types.h>
 
+struct inet_timewait_sock;
+
 /* Driver-facing API */
 struct psp_dev *
 psp_dev_create(struct net_device *netdev, struct psp_dev_ops *psd_ops,
 	       struct psp_dev_caps *psd_caps, void *priv_ptr);
 void psp_dev_unregister(struct psp_dev *psd);
 
+/* Kernel-facing API */
+static inline void psp_sk_assoc_free(struct sock *sk) { }
+static inline void psp_twsk_assoc_free(struct inet_timewait_sock *tw) { }
+
 #endif /* __NET_PSP_HELPERS_H */
diff --git a/include/net/psp/types.h b/include/net/psp/types.h
index d242b1ecee7d..4922fc8d42fd 100644
--- a/include/net/psp/types.h
+++ b/include/net/psp/types.h
@@ -84,6 +84,13 @@ struct psp_dev_caps {
 
 #define PSP_MAX_KEY	32
 
+struct psp_skb_ext {
+	__be32 spi;
+	u16 dev_id;
+	u8 generation;
+	u8 version;
+};
+
 /**
  * struct psp_dev_ops - netdev driver facing PSP callbacks
  */
diff --git a/include/net/sock.h b/include/net/sock.h
index 0fd465935334..d1d3d36e39ae 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -249,6 +249,7 @@ struct sk_filter;
   *	@sk_dst_cache: destination cache
   *	@sk_dst_pending_confirm: need to confirm neighbour
   *	@sk_policy: flow policy
+  *	@psp_assoc: PSP association, if socket is PSP-secured
   *	@sk_receive_queue: incoming packets
   *	@sk_wmem_alloc: transmit queue bytes committed
   *	@sk_tsq_flags: TCP Small Queues flags
@@ -451,6 +452,9 @@ struct sock {
 #ifdef CONFIG_XFRM
 	struct xfrm_policy __rcu *sk_policy[2];
 #endif
+#if IS_ENABLED(CONFIG_INET_PSP)
+	struct psp_assoc __rcu	*psp_assoc;
+#endif
 	struct numa_drop_counters *sk_drop_counters;
 	__cacheline_group_end(sock_read_rxtx);
 
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 23b776cd9879..d331e607edfb 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -79,6 +79,7 @@
 #include <net/mptcp.h>
 #include <net/mctp.h>
 #include <net/page_pool/helpers.h>
+#include <net/psp/types.h>
 #include <net/dropreason.h>
 
 #include <linux/uaccess.h>
@@ -5062,6 +5063,9 @@ static const u8 skb_ext_type_len[] = {
 #if IS_ENABLED(CONFIG_MCTP_FLOWS)
 	[SKB_EXT_MCTP] = SKB_EXT_CHUNKSIZEOF(struct mctp_flow),
 #endif
+#if IS_ENABLED(CONFIG_INET_PSP)
+	[SKB_EXT_PSP] = SKB_EXT_CHUNKSIZEOF(struct psp_skb_ext),
+#endif
 };
 
 static __always_inline unsigned int skb_ext_total_length(void)
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 76e38092cd8a..e298dacb4a06 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -102,6 +102,7 @@
 #include <net/gro.h>
 #include <net/gso.h>
 #include <net/tcp.h>
+#include <net/psp.h>
 #include <net/udp.h>
 #include <net/udplite.h>
 #include <net/ping.h>
@@ -158,6 +159,7 @@ void inet_sock_destruct(struct sock *sk)
 	kfree(rcu_dereference_protected(inet->inet_opt, 1));
 	dst_release(rcu_dereference_protected(sk->sk_dst_cache, 1));
 	dst_release(rcu_dereference_protected(sk->sk_rx_dst, 1));
+	psp_sk_assoc_free(sk);
 }
 EXPORT_SYMBOL(inet_sock_destruct);
 
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index 327095ef95ef..ddb67015ba28 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -24,6 +24,7 @@
 #include <net/xfrm.h>
 #include <net/busy_poll.h>
 #include <net/rstreason.h>
+#include <net/psp.h>
 
 static bool tcp_in_window(u32 seq, u32 end_seq, u32 s_win, u32 e_win)
 {
@@ -392,6 +393,7 @@ void tcp_twsk_destructor(struct sock *sk)
 	}
 #endif
 	tcp_ao_destroy_sock(sk, true);
+	psp_twsk_assoc_free(inet_twsk(sk));
 }
 
 void tcp_twsk_purge(struct list_head *net_exit_list)